It has long been known that explosives and propellants are susceptible to unwanted ignition from electrostatic discharges (ESD), i.e. ESD arcs. Investigation of this phenomena has been active for a long time, but knowledge of the flow, interaction, field, and arc path are virtually nonexistent.
Previously, the only way to determine the path of an arc through a resistive material such as a solid propellant was by observing damage done by the arc. If the damage was large enough, X-raying could partially reveal the path. Dissection of the resistive material might also reveal the path, but this would destroy the sample. Because of these limitations, a need existed for a process for making a map of an arc through a sample of resistive material without any degradation of the sample and without being dependent on the sample being degraded by the arc. Such a process will aid in a better understanding of the ESD phenomena.